I recently setup my Mini connecting to my Premiere via Moca. Now, my internet connection with other devices (laptops) is very slow. If I unplug the coax cable from the Mini, the download speed immediately returns to normal. The difference is very noticeable. Using the speed test at speedtest.net, the download speed changes from 10-20 Mbps to 1 Mbps. Other speed test applications returned similar results. Any ideas what could be causing this?

Sounds like MoCa is causing interference. I think other people who reported this problem ended up returning the Mini and getting another one and it fixed the problem. Your other option is to isolate the coax you use for your cable modem from the MoCa network by using a POE filter. However that may not be possible depending on how your cable is split.

There appear to be two states to my network. One where the Internet connection is very slow (presumably because the MoCA network is interfering with it). In this state the MoCA connection is reliable, and the Tivo Mini functions as expected. The other state has the internet connection functioning as expected, but the MoCA connection is very unreliable. In this state the Mini functions for a few seconds then it loses the connection to the Premiere. Examining the Network status on the Premiere reveals a message that indicates that the "MoCA bandwidth is too low." I assume that is the problem, but it doesn't indicate any solutions. I have ordered a MoCA filter, and I hope that will solve my problem.

This after rebooting the router and both Tivos.

Right now my internet is great, but the Mini doesn't work. I'm not sure how to get to the other state, but I did it once.

Just to follow up to give closure. I installed a filter on my cable modem which should isolate the MoCa network from the Ethernet network. That didn't have any impact. Then, I installed a second filter on the cable as it came into my house. That seemed to solve all the problems. I still have the filter on the modem just because I don't feel like messing with it anymore. It may or may be important.